Grinder for mower-knives.



, 1. E. VOGT. GRINDER FOR MOWER KNIVES. APPLICATION FILED JUNE 2, I914- RENEWED JUNE 2811915.

1,167,862. I Patented Jan. 11, 1916.

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80177265568.- 1 w I 320.5270? /7 E I 5] 0% I J. E. VOGT.

GRINDER FOR MOWER KNIVES.

APPLICATION FlLED-JUNE2.19I4. RENEWED JUNE 28, I915.

Patented Jan. 11, 1916. E

2 SHEETS-SHEET 2.

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COLUMBIA PLANOGRAPH co., WASHINGTON. n. c.

invrrnp stares parent orat on,

JOHN E. veer, or (intense, ILLINOIS..

GRINDER FOB MOWER-KNIVES.

Specificationof Letters Patent.

Application filed June 2, 1914, Serial No. 842,450. Renewed June 28, 1915. Serial No; 36,909.

To all whom it may concern:

Be it known that 1, JOHN E. Voo'r, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and use ful Improvements in Grinders, for Mower- Knives; and 1 do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable otaers skilled in the art to which it appertains to make and use the same.

My invention relates to the class of grinding machines used for. sharpening the toothed sections of mowing and harvesting machine knives. In grinding knives of this class, it is desirable to provide each tooth with a cutting edge presenting a different angle at its tip from that presented at its more rearward or broader portions.

One object of my invention is to provide a grinding machine equipped with means for automatically shifting the point of contact between the grinding wheel and the knife blade so as to successively sharpen all of the portions of the cutting edge of each adjacent pair of teeth.

Another object is to provide means for adjusting the said movement of the blade to adapt the grinder to the sharpening of teeth of different depths, and also to adjust the travel to that reouired for a given depth of teeth when the abrasive wheel is reduced in si7e by its normal wear.

Still another object is to provide simple eans for supporting the blade out of contact with the wheel and'in convenient position for inspecting the freshly sharpened surface.

Other obiects will appear from the following specification and from the accompanving drawings, in -which Figure 1 is a side elevation of a grinder embodying my invention. Fig. 2 is a plan view of the same. Fig. 3 is a fragmentary side ele ation showing the range of movement of the blade-holder,

In the drawings, my invention is shown as applied to an abrasive wheel 1 mounted upon a shaft 2 extending through alined bearings 3 upon the upper edge of a trough lsupported by legs 5, which legs in turn are connected by braces 6. Pivotally connected to two of the laterally opposed legs 6 by pivots 7 is a substantially U-shaped rocking member 8, which member is preferably curved substantially in conformity with the 7 adjacent edge portion of the trough 4:. The

rocking member 8 has each shank thereof equipped near 1ts i3121IlSV6IS8 13OItlO11 9-w1th a pair of alined perforations, while one shank of the said member 8 is equipped with a plurality of perforations 1O spaced at varyin g distances from the said pivot 7. Mount- .ed upon the shaft 2 and preferably between the abrasive wheel 1 and one of the bearings 3 is an eccentric 11 carrying a strap 12 rigidly secured to an eccentric rod 18. The rod 13 is also equipped with a series of perforations 14, through any one of which the said rod may be pivotally connected to the rocking member 8 by a bolt extending also through one of the said perforations 10. Extending transversely through the said alined perforations in the shanks of the rocking member 8 is a rod 16 connecting the two ends of a forked member 17. which member has a clamp portion 18 secured thereto by a screw 19, opposed portions of the said members 18 and .19 being adapted to clamp a blade 20 therebetween. The arms of the forked member 17 are of such length that the toothed portions of the blade 20 will bear continually and by gravity against the edge portions of the wheel 1, as shown in the drawings. However, when the wheel 1 is rotated by suitable means, such as'the pulley 21 mounted upon one end of the shaft 2-, the eccentric 11, strap 12 and rod 13 will coact to cause the rocking member 8 to oscillate about its pivotal mounting 7 thereby moving the blade-holder with respect to the wheel (as shown in Fi 3) and causing the said holder to successively present different portions of the blade to the edge of the wheel as the latter is rotated. By shifting the pivo al connection between the rod 13 Patented Jan. 11, 1916.

and the rocking member 8 from one toanother of the perforations in the said respecti ve members, the extent of oscillation of the blade-holder can readily be varied, as also the angle at which the blade bears against the wheel when the holder is in any given point of its travel. Consequently, the holder can readily be adjusted so as to insure an effective grinding for all of the cutting portions of the blade, regardless of the size of the teeth of the said blade and of the diameter of the wheel.

While it will be obvious that upon a continued rotation of the wheel 1. the eccentric and the rocking member oscillated thereby will continually shift the blade-holder so as to efi'ect the grinding of different portions of the teeth, it may not be advisable to depend merely upon a given number of rotations of the wheel for effecting the desired amount of grinding. I, therefore, preferably equip the bladeholder of my .machine with an auxiliary rod 22 extending between the forks 17 parallel to the rod 15, this rod being so disposed as to be normally out of contact with the transverse portion 9 of the rocking member 8. Upon tipping the bladeholder back manually (as shown in dotted lines in F ig. l), the said auxiliary rod 22 will engage the said transverse portion 9 of the rocking member, thereby acting as a stop for the rearward motion of the bladeholder and enabling the latter to be maintained by gravity in the position shown in dotted lines in Fig. 1, that is to say when the blade-holder has been moved about the rod 15 so as to bring the center of gravity of the blade-holder beyond said rod. It will be obvious from the drawings that the blade when in this position may readily be inspected, and it will likewise be obvious that when the bladeholder is thus tipped up to bring the blade out of contact with the wheel, the holder may readily be slid laterally of the rocking member 8 so as to bring the wheel successively into grinding relation to other pairs of teeth upon the blade. It will also be obvious that by making the rocking member 8 out of bar steel, I can provide both a simple and light but strong construction. However, I do not wish to be limited to this particular construction of the rocking member, nor to the particular arrangement as described for the cooperating formations of the blade-holder and the rocking member, since both these and other details might be varied greatly without departing from the spirit of my invention.

I claim as my invention l. A grinder including a supporting member a shaft carried thereby, an abrasive wheel and an eccentric both rotatably mounted upon the shaft, a bifurcated member straddling the said supporting member and pivotally joined thereto at the ends of its forks and equipped with alined perforations in its forks; connections between the eccentric and the bifurcated member for causing the rotation of the former to oscillate the latter about its said pivotal junctions, a rod slidably extending through the said alined perforations in the forks of the bifurcated member and substantially parallel to said shaft, and a blade-holder pivotally carried by said rod.

2. A grinder including a supporting member, a shaft carried thereby, an abrasive wheel and an eccentric both rotatably mounted upon the shaft, a bifurcated member straddling the said supporting member and pivotally joined thereto at the ends of its forks and equipped with alined perforations in its forks; connections between the eccentric and the bifurcated member for causing the rotation of'the former to oscillate the latter about its said pivotal junctions, a rod slidably extending through the said alined perforations in the forks of the bifurcated member and substantially parallel to said shaft, a blade-holder pivotally carried by said rod; and means associated with the blade-holder and bifurcated member for holding the said bladeholder in a position in which the blade mounted there on is out of contact with the abrasive wheel when the blade-holder is moved about said rod to bring the center of gravity of the blade-holder beyond said rod.

3. A grinder including a supporting member, a shaft carried thereby, an abrasive wheel and an eccentric both rotatably mounted upon the shaft, a bifurcated member straddling the said supporting member and pivotally joined thereto at the ends of its forks and equipped with alined perforations in its forks; connections between the eccentric and the bifurcated member for causing the rotation of the former to oscillate the latter about its said pivotal junctions, and a blade-holding member including a pair of parallel rods, one thereof eX- tending through the said perforations in the bifurcated member, the other thereof adapted to bear against a portion of the said bifurcated member to support the bladeholder in a position in which the blade carried thereby is out of contact with the abrasive wheel.

In testimony whereof, I have signed my name 1n presence of two subscribing witnesses.

JOHN E. VOGT. Witnesses:

ALBERT SCHEIBLE, M. M. BOYLE.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. C. 

